Detecting the stages of hyperplasia formation in the breast ducts using ultrasound B-scan images

Presented at the 2006 3rd IEEE International Symposium on Biomedical Imaging: From Nano to Macro, Arlington, VA, DOI: http://dx.doi.org/10.1109/ISBI.2006.1625064A stochastic decomposition algorithm of the RF Echo into its coherent and diffuse components is used towards estimating the structural parameters of the hyperplastic stages of the breast tissue leading to early breast cancer detection. The discrimination power of the various parameters is studied under a host of conditions such as varying resolution and SNR values using a point scatterer model simulator that mimics epithelium hyperplastic growth in the breast ducts. It is shown that three parameters, in particular, the number of coherent scatterers, the Rayleigh scattering degree and the energy of the diffuse scatterers, prove to show very high ability to discriminate between various stages of hyperplasia even in cases of low resolution and SNR values. Values of Az>0.942 were obtained for resolution less than or equal to 0.4mm even in low SNR values, then it drops below the 0.9 range as the resolution exceeds the 0.4mm range

Non-Cancerous Abnormalities That Could Mimic Prostate Cancer Like Signal in Multi-Parametric MRI Images

Prostate Cancer (PCa) is the most common non-cutaneous cancer in North American men. Multi-parametric magnatic resonance imaging (mpMRI) has the potential to be used as a non-invasive procedure to predict locations and prognosis of PCa. This study aims to examine non-cancerous pathology lesions and normal histology that could mimic cancer in mpMRI signals. This study includes 19 radical prostatectomy specimens from the London Health Science Centre (LHSC) that were marked with 10 strand-shaped fiducials per specimen which were used as landmarks in histology processing and ex vivo MRI. Initial registration between fiducials on histology and MR images was performed followed by the development of an interactive digital technique for deformable registration of in vivo to ex vivo MRI with digital histopathology images. The relationship between MRI signals and non-cancerous abnormalities that could mimic PCa has not been tested previously in correlation with digital histopathology imaging. The unregistered mp-MRI images are contoured by 4 individual radiology observers according to the Prostate Imaging Reporting and Data System (PI-RADS). Analysis of the radiology data showed prostatic intraepithelial neoplasia (PIN), atrophy and benign prostatic hyperplasia (BPH) as main non-cancerous abnormalities responsible for cancer like signals on mpMRI. This study will help increase the accuracy of detecting PCa and play a role in the diagnosis and classification of confounders that mimic cancer in MR images

Imaging of the Breast

Early detection of breast cancer combined with targeted therapy offers the best outcome for breast cancer patients. This volume deal with a wide range of new technical innovations for improving breast cancer detection, diagnosis and therapy. There is a special focus on improvements in mammographic image quality, image analysis, magnetic resonance imaging of the breast and molecular imaging. A chapter on targeted therapy explores the option of less radical postoperative therapy for women with early, screen-detected breast cancers

Ultrasound-based assessment and management of postmenopausal bleeding and endometrial polyps

This thesis has evaluated aspects of ultrasound-based assessment and management of women with postmenopausal bleeding and endometrial polyps. The efficacy of transrectal ultrasound scan (TRS) was assessed in 103 consecutive postmenopausal women with an axial uterus. TRS was accepted by two-thirds of the women and the proportion of satisfactory endometrial assessments was significantly higher on TRS compared to transvaginal scan (TVS), 91% (95% CI 84-98) vs 62% (95% CI 50-74), respectively. In the subgroup of 50 women with postmenopausal bleeding and an axial uterus, the endometrial thickness measured significantly thinner on TRS by a median of 1.2mm (IQR 0.4-3) compared to TVS. Furthermore, subjective pattern recognition for endometrial cancer was less accurate on TVS compared to TRS when the uterus is in an axial position. The interrater reliability of ultrasound subjective pattern recognition for endometrial cancer was prospectively assessed in 40 women with postmenopausal bleeding and a thickened endometrium (≥4.5mm); a good level of agreement (κ = 0.78, 95% CI 0.61-0.95) was found between an expert and an average operator. The diagnostic accuracy of ultrasound subjective pattern recognition for endometrial cancer was assessed in 240 consecutive women with postmenopausal bleeding and a thickened endometrium (≥4.5mm) and available histology. It performed well with a sensitivity and specificity of 88% (95% CI 77-95) and 97% (95% CI 94-99), respectively. The presence of focal malignancy within endometrial polyps was the most common cause of a false-negative diagnosis of endometrial cancer. Endometrial cancer was diagnosed on ultrasound by subjective pattern recognition and simultaneously assessed for the presence of deep myometrial invasion and cervical stromal invasion in 51 women. We found that the accuracy of ultrasound in the preoperative staging of endometrial cancer was comparable to MRI (sensitivity and specificity, 86% vs 77% and 66% vs 76%, respectively). A clinical model was presented to estimate the risk (low, intermediate, or high) of pre-malignancy or malignancy in postmenopausal endometrial polyps. The model included polyp size, the presence or absence of intralesional cystic spaces and the patient’s BMI as clinical variables. Accordingly, approximately one-third of postmenopausal polyps would be categorised as high- or intermediate-risk and they would account for over 90% of all premalignant/malignant polyps, while the remaining polyps would be categorised as low-risk with a 1/18 risk of pre-malignancy or malignancy. The overall accuracy of the model in predicting premalignant or malignant postmenopausal polyps was 92% (95% CI 86.0-97.4). The natural history of expectantly managed endometrial polyps was assessed retrospectively in 112 polyps over a median follow-up of 22.5 months (range 6-136). We found that polyps’ growth rates varied, and it was not possible to predict an individual polyp’s growth based on the patient’s clinical characteristics or polyp’s morphological features. Polyp’s growth rate was not associated with the risk of developing abnormal uterine bleeding (AUB). Some polyps underwent spontaneous regression (7/112, 6%) and this occurred more frequently among premenopausal women and those who were symptomatic of AUB

Multiparametric 3 Tesla magnetic resonance imaging as a clinical tool to characterize prostate cancer

Scientists have come a long way in understanding prostate cancer as a disease and how its progression affects the men who develop it. Prostate adenocarcinoma may be present without causing clinical symptoms. Prostate cancer may metastasize, which increases the likelihood of fatality. The cause of the disease is still not completely clear, but genetics, race, tissue damage, history of previous infections, diet, and environmental influences appear to play a role in its development. Magnetic resonance imaging (MRI) has become an excellent clinical tool to characterize prostate cancer without the use of ionizing radiation or surgery. It is concluded that MRI is the optimal imaging modality to achieve detection, characterization, and staging of intracapsular and extracapsular prostate disease. The advances in MRI technology, particularly 3 Tesla, allows for reduced surgical intervention thus improving quality of life for patients with the disease

Ultrahigh resolution optical coherence tomography for the detection of early stage neoplastic pathologies

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.Includes bibliographical references (p. 105-118).Identification of changes associated with early stage disease remains a critical objective of clinical detection and treatment. Effective screening and detection is important for improving outcome because advanced disease, such as metastatic cancer, can be difficult to impossible to cure. Many existing diagnostic modalities, including x-ray imaging, magnetic resonance imaging, ultrasound, and endoscopy do not have sufficient resolution to detect changes in architectural morphology associated with early neoplasia and other pathologies. Diagnostic modalities capable of identifying pre-malignant tissue at an early stage could therefore significantly improve treatment outcome. Optical coherence tomography (OCT) is an emerging biomedical imaging technique that can potentially be used as an in vivo tool for identifying early stage neoplastic pathologies. Recent advances in solid-state laser and nonlinear fiber technology have enabled the development of ultrahigh resolution and spectroscopic OCT techniques which promise to improve tissue differentiation and image contrast. Previous ex vivo, benchtop ultrahigh resolution OCT imaging studies suggest that differentiation of architectural morphology associated with pathology is feasible. This thesis covers the development and investigation of ultrahigh resolution OCT for studies of early neoplastic pathologies.(cont.) A section of this thesis will focus on development and evaluation of a novel turn-key broadband source for OCT. Feasibility studies were performed using ultrahigh resolution OCT for imaging human tissues ex vivo in the clinical pathology laboratory setting. Imaging results will be presented examining a variety of normal and neoplastic lesions in preliminary studies of the thyroid gland, large and small intestine, and breast. These experiments elucidate the optimal imaging parameters, potential and limitations of the technique, and establish the microstructural markers visible in OCT images that are characteristic of pathologic tissues. These studies establish a baseline which should help interpret future in vivo ultrahigh resolution OCT imaging studies.by Pei-Lin Hsiung.Ph.D

Imaging in Women\u27s Health

Women’s health is a large area of the medical field that is continuing to see growth and technological advancement. Gynecological, obstetric, and breast health are fields that are always in demand, and imaging plays a large role in caring for patients in these fields. This paper will discuss different areas of women’s health and explain how imaging can be used to assist in diagnosis and treatment. Imaging can include MRI, 2D ultrasound, 3D ultrasound, and x-ray. This paper will discuss basic gynecological health, complications that can arise in gynecological health, women’s health in college, preconception care, obstetrics, obstetric complications, breast health, post menopausal health, and other women’s health issues. Some topics discussed will be endometriosis, adenomyosis, breast cancer screening and treatment, endometrial cancer, pregnancy, pelvic floor health, and ovarian masses. It will also discuss the future of women’s health. From basic gynecological health through pregnancy, breast health and menopause, imaging is a vital tool used to help medical professionals diagnose, monitor and treat women through many stages of life

Comments and illustrations of the WFUMB CEUS liver guidelines: Rare benign focal liver lesion, part I.

Improved detection and characterization of common focal liver lesions (FLL) are the main topics of the World Federation for Ultrasound in Medicine and Biology (WFUMB) guidelines on the use of contrast-enhanced ultrasound (CEUS). On stateof-the-art CEUS imaging, to create a library of rare FLL, especially concerning their atypical imaging characteristics, might be helpful for improving clinical diagnostic efficiency. In this review, we aim to summarize the ultrasound and CEUS features of rare benign FLL. Currently there are limited reports and images published

High-resolution fluorescence endomicroscopy for rapid evaluation of breast cancer margins

Breast cancer is a major public health problem world-wide and the second leading cause of cancer-related female deaths. Breast conserving surgery (BCS), in the form of wide local excision (WLE), allows complete tumour resection while maintaining acceptable cosmesis. It is the recommended treatment for a large number of patients with early stage disease or, in more advanced cases, following neoadjuvant chemotherapy. About 30% of patients undergoing BCS require one or more re-operative interventions, mainly due to the presence of positive margins. The standard of care for surgical margin assessment is post-operative examination of histopathological tissue sections. However, this process is invasive, introduces sampling errors and does not provide real-time assessment of the tumour status of radial margins. The objective of this thesis is to improve intra-operative assessment of margin status by performing optical biopsy in breast tissue. This thesis presents several technical and clinical developments related to confocal fluorescence endomicroscopy systems for real-time characterisation of different breast morphologies. The imaging systems discussed employ flexible fibre-bundle based imaging probes coupled to high-speed line-scan confocal microscope set-up. A preliminary study on 43 unfixed breast specimens describes the development and testing of line-scan confocal laser endomicroscope (LS-CLE) to image and classify different breast pathologies. LS-CLE is also demonstrated to assess the intra-operative tumour status of whole WLE specimens and surgical excisions with high diagnostic accuracy. A third study demonstrates the development and testing of a bespoke LS-CLE system with methylene blue (MB), an US Food and Drug Administration (FDA) approved fluorescent agent, and integration with robotic scanner to enable large-area in vivo imaging of breast cancer. The work also addresses three technical issues which limit existing fibre-bundle based fluorescence endomicroscopy systems: i) Restriction to use single fluorescence agent due to low-speed, single excitation and single fluorescence spectral band imaging systems; ii) Limited Field of view (FOV) of fibre-bundle endomicroscopes due to small size of the fibre tip and iii) Limited spatial resolution of fibre-bundle endomicroscopes due to the spacing between the individual fibres leading to fibre-pixelation effects. Details of design and development of a high-speed dual-wavelength LS-CLE system suitable for high-resolution multiplexed imaging are presented. Dual-wavelength imaging is achieved by sequentially switching between 488 nm and 660 nm laser sources for alternate frames, avoiding spectral bleed-through, and providing an effective frame rate of 60 Hz. A combination of hand-held or robotic scanning with real-time video mosaicking, is demonstrated to enable large-area imaging while still maintaining microscopic resolution. Finally, a miniaturised piezoelectric transducer-based fibre-shifting endomicroscope is developed to enhance the resolution over conventional fibre-bundle based imaging systems. The fibre-shifting endomicroscope provides a two-fold improvement in resolution and coupled to a high-speed LS-CLE scanning system, provides real-time imaging of biological samples at 30 fps. These investigations furthered the utility and applications of the fibre-bundle based fluorescence systems for rapid imaging and diagnosis of cancer margins.Open Acces